Std Single Frequency With Bottom Discrimination Mode; Dual Frequency Mixed Mode - JRC FF50 Instruction Manual

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STD Single Frequency with Bottom
Discrimination Mode
• Select STD/BTM DISCRIM to divide the screen vertically in two in
the ratio of 1:1. It shows the high or low frequency standard display
on the right side of the screen. The magnified display of the area just
above the seabed shows on the top half of the left side. The bottom
half of the left side shows the standard display of the sea bottom, with
the sea bottom surface in the center. In this mode, the bottom line is
displayed with respect to the sea surface as a reference. Therefore, it is
easy to check the bottom line. In general, a narrow bottom line
indicates that the seabed is hard and a thick bottom line indicates a
soft seabed. This mode is recommended when you want to roughly
determine seabed conditions such as rock, sand or mud.
Push to toggle between the high and low frequencies.

Dual Frequency Mixed Mode

• Select STD/MIX to divide the screen vertically in two in the ratio of
1:1. It shows the high frequency preferred or low frequency preferred
mixed display on the right side of the screen and the standard display
of the frequency other than that used for the mixed display on the left
side of the screen. In the preferred mixed display, echoes of only one
of the frequencies are displayed in the normal color and echoes of
both frequencies are displayed in the color of the maximum level. The
strength of echoes of fish differ depending on the frequencies. In other
words, echoes of schools of fish are displayed differently for each
frequency. For example, the echoes of small marine life, such as
shrimp, may be obscure in the low frequency, but echoes of a large
fish such as tuna are clearly visible in both high and low frequencies.
Therefore, the echoes displayed in the normal color on the high
frequency preferred mixed display may be regarded as small fish. On
the other hand, the beam of the Transducer connected to the FF50 is
narrow in the high frequency and wide in the low frequency. Echoes
of schools of fish near the vertical line from the Transducer may be
displayed in both high and low frequencies, and echoes of schools of
fish away from the line are probably displayed only in the low
frequency. Therefore echoes displayed in the normal color on the low
frequency preferred mixed display can be regarded as those of fish
away from your vessel.
Push to toggle between the high and low frequencies.